I recently griped about rabbits on this blog, but there is another creature that I find far more annoying, and that is Glechoma hederacea, commonly known as ground ivy, creeping Charlie, or cat’s-foot. This little perennial weed has invaded my gardens from my not very well-tended lawn, and it seems to me that it re-grows there as fast as I pull it out!
Ground ivy sprawls along the ground , so mowing doesn’t affect it at all. It is very easy to recognize since, like other members of the mint family, its stems are square. Each “mother plant” sends out long runners (stolons), and at each stem node, fibrous roots emerge into the soil and 2 opposite leaves emerge above ground. The leaves are rounded or heart-shaped with scalloped edges, and each is attached to its own long petiole. Leaves and stems may have short hairs. This plant tends to remain green year-round. When crushed, ground ivy has a minty smell. Though it produces seeds from small purplish-blue tubular flowers in the spring, it propagates itself more often asexually via its stolons. When hand-pulling, you must make certain to get the whole plant since pieces left behind will continue to grow and send out runners.
Ground ivy originated in Europe, and, like many other weeds, it was intentionally brought to this country by early settlers who used it for medicinal purposes as a tea, tonic, poultice or herbal remedy for many ills. It was also used by early Saxons in beer making. and so is sometimes called alehoof or tun-hoof.
Ground ivy likes growing in shady, damp conditions, but it will also tolerate sun, especially in thin lawns. Besides hand pulling, it can be controlled by combing through the lawn with a de-thatching rake, though this is labor-intensive and will remove some grass as well. It will be unlikely to take a foothold in thick turf so maintaining a healthy lawn by following proper mowing, watering and fertilizing techniques is an important solution to the problem. According to Penn State, post-emergent herbicides that combine 2,4-D with dicamba and MCPP/MCPA are most effective against this weed with late summer to early fall as optimal application time. Be aware that this combination will also kill other broad-leaved or woody plants so it must be applied with caution, and you only want to spray enough to wet the leaves of the ground ivy since dicamba can be absorbed by the roots of desirable plants if it gets into the soil! Always follow label instructions carefully. Shady areas that prohibit grass growth might have to be replanted with a suitable shade ground cover. As an alternative, there are some gardeners who like ground ivy as a good native ground cover since it tends to fill in rapidly in those areas. There is actually a variegated form Glechoma ‘Variegata’ sold by some nurseries as a ground cover or for hanging containers. More detailed information on ground ivy can be found here:
As for me, if I can somehow entice those darn rabbits into eating the ground ivy instead of my garden plants, then I’ll have solved two problems!